The invention relates to novel substituted and unsubstituted 13-(alkoxy)methoxy avermectin aglycone derivatives useful as antiparasitic agents and to the novel intermediates useful in the process for preparing said derivatives. This invention also relates to compositions of said derivatives and methods of administering said compositions.
The term avermectin (previously referred to as C-076) is used to describe a series of compounds isolated from the fermentation broth of an avermectin producing strain of Streptomyces avermitilis and derivatives thereof. The morphological characteristics of the culture are completely described in U.S. Pat. No. 4,310,519 and are incorporated herein by reference. The avermectin compounds are a series of macrolides, each of which is substituted thereon at the 13-position with a 4'-(.alpha.-L-oleandrosyl)-.alpha.-L-oleandrose group. Avermectin compounds and the derivatives thereof of this invention have a very high degree of anthelmintic and antiparasitic activity.